Russian opposition leader Alexei Navalny is being transferred to a single-cell room for one year, Navalny wrote on the social media platform X, formerly known as Twitter, on Sept. 27.
The news comes after Judge Viktor Rogov of the Moscow City Court rejected Navalny's appeal against a 19-year sentence on extremism charges handed to him on Aug. 4, Russian state news agency RIA Novosti reported.
That sentence is on top of the 11-and-a-half years Navalny is currently serving in a maximum security prison after being convicted in 2020 for fraud and other charges, all of which he denies.
The court on Sept. 27 also denied an appeal by Daniel Kholodny, a TV producer who worked for Navalny's YouTube channel and who was also sentenced in August to eight years in prison in the same case.
Navalny described the new cell he was to be held in as "the strictest possible punishment in all kinds of prisons."
The August sentence already called for Navalny to serve his time in a "special regime colony," Russia's most restrictive penal institution usually reserved for dangerous criminals.
After the announcement in August, Navalny posted on Twitter that, "the number (of years) doesn't matter. I understand very well that, like many political prisoners, I am serving a life sentence. Where life is measured by the duration of my life or the life of this regime."
The European Union, the U.S., and the U.K. criticized the court's sentence as politically motivated and demanded the immediate release of Navalny.